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A glaucoma glossary

Anterior chamber The part of the eye between the cornea and iris, filled with aqueous humor.

Aqueous humor A clear gelatinous-like fluid continually produced in the eye’s anterior chamber. This fluid exits the eye via drainage canals in a region called the anterior chamber angle.

Glaucoma A complex eye disease characterized by optic nerve damage and resulting loss of vision. Abnormally high pressure within the eye is usually, but not always, present in the condition.

Intraocular pressure (IOP) The pressure inside the eye that results from the combined production and drainage of aqueous humor, measured in millimeters of mercury (mmHg). Normal IOP ranges between 10 and 21 mmHg.

Laser trabeculoplasty A laser beam procedure that targets the eye’s drainage channels to improve flow and lower intraocular pressure.

Optic nerve The nerve tract that transmits visual information from the retina to the brain.

Optic head drusen Calcified deposits in the region where the optic nerve enters the back of the eye. Optic head drusen are associated with visual field loss, and may be present in glaucoma.

Shunt An artificial drainage device surgically implanted in the eye to lower intraocular pressure. The SOLX shunt, still in clinical trials, is made of inert, highly purified gold. The SOLX device is far smaller than conventional shunts and can be quickly implanted in a minimally invasive procedure.

Trabecular meshwork Cellular tissue in the anterior angle chamber that allows aqueous humor to drain from inside the eye.

Trabectome A recently developed, minimally invasive procedure that removes sections of the trabecular meshwork that are damaged in glaucoma.

Trabeculectomy A well-established surgical treatment for glaucoma, in which a small drainage hole is created in the sclera (“white”) of the eye. The surgery carries some risks, and may need to be repeated if the drainage hole becomes obstructed by scar tissue.